[백준] 2839번 설탕 배달 c++

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main(void) {
	ios::sync_with_stdio(NULL);
	cin.tie(NULL);
	cout.tie(NULL);
	vector<int> v;
	int N;
	cin >> N;
	for (int i = 0; i <= N / 5; i++) {
		for (int j = 0; j <= N / 3; j++) {
			if (5 * i + 3 * j == N)
				v.push_back(i + j);
		}
	}
	sort(v.begin(), v.end());
	if (v.size()) cout << v[0];
	else cout << -1;
}